Power consumption continues to be an important aspect of Digital Signal Processing (DSP) systems. Wireless communication domain is an important sector for Digital Signal Processing (DSP) applications. Most wireless terminals are supplied by battery. The design of low power terminals is one of the key challenges in this domain. New services are provided (image, video, Internet access) and require high data rate. Consequently, the complexity of the baseband digital part is growing. However, the energy consumption cannot be increased due to the limited battery lifetime. Thus, new strategies to reduce or maintain the energy consumption power at a reasonable level must be proposed.
The energy consumption of an application depends on the word-length of the manipulated data. The energy consumption can be reduced by decreasing the data wordlength. Nevertheless, this also reduces the computation accuracy and increases the unavoidable error due to finite word-length computation. In traditional design of DSP systems, fixed word lengths optimized for optimum performance in high signal quality scenarios are used. However, the system is often noise and/or interferer limited which leads to a signal quality which is way lower than optimum and hence in such scenarios, word length can be reduced without major impact on the overall signal quality.